Speaking to reporters here, Shinde said one should not make anti-law remarks.
"One has to make such statements carefully. One should not say those things which do not fall under the ambit of law," Shinde said in response to a question about controversial remarks made by Modi and Gandhi.
Both Gandhi and Modi landed in controversy over their election rally speeches.
Gandhi was served a notice by the Election Commission on a Bharatiya Janata Party (BJP) complaint over his rallies in Rajasthan and Madhya Pradesh. Gandhi replied to the notice last week.
Shinde said one should not make anti-law remarks.
The BJP had told the poll panel that Gandhi violated the model code by accusing it of instigating communal riots. Gandhi also said Pakistan's Inter Services Intelligence (ISI) was trying to reach out to Muslims affected by September's Muzaffarnagar riots.
The Congress also moved the commission last week demanding stern action against Modi over his "khooni panja" (bloody hand) barb at a rally in poll-bound Chhattisgarh.
Shinde did not answer a specific query about Gandhi's remarks about ISI trying to get in touch with some Muzaffarnagar riot victims.
"I have said on a number of occasions that I have nothing to say on this," he said.
Shinde, however, dismissed Modi's allegations at a rally that those who had been able to defeat him politically were misusing the Central Bureau of Investigation (CBI) and had given a free hand to the Indian Mujahideen (IM).
"Narendra Modi is speaking just like that. Does it happen like that. CBI is an independent body. Such allegations are not good," he said.
"If they (IM) would have gone by what we say, there would have been riots. How such a thing came to Modi's mind, we do not know," Shinde said.