Reference for Keritot 3:1
אָמְרוּ לוֹ אָכַלְתָּ חֵלֶב, מֵבִיא חַטָּאת. עֵד אוֹמֵר אָכַל וְעֵד אוֹמֵר לֹא אָכַל, אִשָּׁה אוֹמֶרֶת אָכַל וְאִשָּׁה אוֹמֶרֶת לֹא אָכַל, מֵבִיא אָשָׁם תָּלוּי. עֵד אוֹמֵר אָכַל וְהוּא אוֹמֵר לֹא אָכַלְתִּי, פָּטוּר. שְׁנַיִם אוֹמְרִים אָכַל וְהוּא אוֹמֵר לֹא אָכַלְתִּי, רַבִּי מֵאִיר מְחַיֵּב. אָמַר רַבִּי מֵאִיר, אִם הֱבִיאוּהוּ שְׁנַיִם לְמִיתָה חֲמוּרָה, לֹא יְבִיאוּהוּ לְקָרְבָּן הַקַּל. אָמְרוּ לוֹ, מָה אִם יִרְצֶה לוֹמַר מֵזִיד הָיִיתִי:
If they [witnesses] said to an individual: You ate forbidden fat, he is liable for a <i>Chattat</i> [an offering brought to expiate sin]. If one witness says he ate, and [another] witness says he did not eat; or if a woman says he ate, and [another] woman says he did not eat, he is liable for an <i>Asham Talui</i> [a guilt-offering brought upon possible commission of a sin]. If one witness says he ate, and he [himself] says, "I did not eat," he is exempt. [If] two [witnesses] say he ate, and he [himself] says, "I did not eat," Rabbi Meir deems him is liable. Rabbi Meir said: Since two [witnesses are capable of] bringing upon him the severe [penalty] of death, can they not bring upon him the less severe [punishment of] a sacrifice? They [the Sages] said to him: Could he not argue, "I did it intentionally"?