It is clear from the Talmud that rice is permissible for consumption on Pesah. The Gemara in Masechet Pesahim relates that one of the Amora’im would eat "Aroza" (rice) at the Seder as one of the foods eaten to commemorate the sacrifices that were offered in the Temple on Pesah night. Furthermore, the Gemara addresses the question of whether one may fulfill the Misva of Masa by eating bread made from rice. The Gemara rules that one does not fulfill the Misva with this kind of Masa, because rice is not included among the five principal grains. Clearly, the Gemara accepted the premise that rice does not constitute Hametz, and it disqualified rice for Masa only because the Masa must be made from one of the five grains. Fundamentally, then, there is no question that rice is permissible on Pesah and is not considered Hametz.
The custom among many communities not to eat rice on Hametz began two or three centuries ago, when the concern arose that some wheat kernels might have been mixed together with the rice. It became common in some countries for wheat fields and rice fields to be situated near one another, and often the same bags were used for the collection of the wheat and the rice. The bags were not always carefully cleaned in between the collections, and it was therefore quite common for one to find kernels of wheat in the packages of rice purchased at the grocery. For this reason, Ashkenazic Jews accepted the custom not to eat rice on Pesah. In Sephardic lands, by and large, there was no concern of wheat kernels being mixed with rice, and therefore the Sepharadim, for the most part, did not accept this custom. A notable exception is the Peri Hadash (Rav Hizkiya Da Silva, 1659-1698), a Sephardic Rabbi who was once eating rice on Pesah and discovered a kernel of wheat mixed in with the rice. At that moment, he took upon himself the custom to refrain from rice on Pesah.
Nevertheless, as mentioned, the accepted custom among most Sepharadim (including our community) is to allow eating rice on Pesah, on condition that it is first checked three times to ensure that there are no wheat kernels. Although it is unclear how and why wheat kernels make their way into packages of rice, this does happen on occasion, and therefore one may not eat rice on Pesah unless it has been carefully inspected. One spreads the rice out on a white surface, so that any dark kernels will be visible and evident, and he checks the rice three times. It is preferable not to perform all three inspections in immediate succession, as he may grow fatigued after the first or second time and not inspect properly. One may not trust a minor below the age of Bar Misva or Bat Misva to perform this inspection.
Ashkenazim must follow their ancestors’ custom not to eat rice on Pesah. Although the Hacham Sevi (Rabbi Tzvi Ashkenazi of Amsterdam, 1660-1718) wrote that he would abolish this custom if he had the authority to do so, since rice was a basic staple, nevertheless, the custom was accepted by all Ashkenazic communities, and Ashkenazim are therefore bound by this prohibition. An Ashkenazi may, however, eat food that was cooked in a pot that had been used for rice. Since even Ashkenazim do not actually consider rice Hametz, they do not treat pots used for Hametz as Hametz pots.
If a Sephardic man marries an Ashkenazic woman, the woman assumes the customs of her Sephardic husband, and she may therefore eat rice on Pesah. Even though she had been raised in an Ashkenazic home and had never eaten rice on Pesah, once she marries a Sepharadi she follows his customs. Conversely, if a Sepharadic woman marries an Ashkenazic man, she may no longer eat rice on Pesah, since she is now married to an Ashkenazi. However, Hacham Ovadia Yosef rules that if the couple visits the wife’s parents on Pesah, and they live in Eretz Yisrael, then she may eat rice in her parents’ home. Since Maran (author of the Shulhan Aruch) is considered the authoritative Halachic decisor for Eretz Yisrael, his rulings are considered the "local custom" even for a woman who marries an Ashkenazi. Although we will not extend this concept to allow her to eat rice on Pesah in her home, since she is married to an Ashkenazi, she may eat rice on Pesah when she is in her parents’ home. Her husband, however, may not eat rice on Pesah even when they visit her parents.
It should be noted that Carolina Rice needs a Hashgacha for Pesah.
Summary: Ashkenazim follow the custom not to eat rice on Pesah, but most Sepharadim, including our community, allow eating rice on Pesah provided that it was first checked three times to ensure that no wheat kernels are mixed in with the rice. An Ashkenazic woman who marries a Sephardic man may eat rice on Pesah, and a Sephardic woman who marries an Ashkenazic man may not eat rice on Pesah unless she is visiting her parents’ home in Israel.