The process was started by the Minister of Jerusalem Affairs, Ze'ev Elkin, after the Balad party member was indicted by the attorney general for allegedly passing mobile phones to Palestinian prisoners.
The Knesset's own legal advisor, Eyal Yanoun, said the process may be struck down as it lacks a "solid legal basis" due to a lack of "sufficient evidence".
Yanoun said that the exclusion process could only be started by charges related to the incitement of racism, spying or "assisting a terrorist organisation against the State of Israel", adding that Ghattas' impending trial does not meet these conditions.
Elkin collected 71 signatures from Knesset members in support of the process to expel Ghattas.
Ghattas was arrested after Israeli prison guard found 12 mobile phones in the cells of two Palestinian prisoners that Ghattas had visited hours previously. Ghattas denies any wrongdoing and has described his arrest as political persecution.Ghattas' lawyer, Leah Tsemel, has condemned the charges, asking why the MK was not searched before he entered the prison.
As a member of the Palestinian-Israeli party, Balad, Ghattas has frequently fought with the Israeli government on issues related to Palestinian rights.