Is smoothing a causal transformation?

Question

After looking at such a plot, I'm asked if my smoothing is causal.

Once, during pre-processing, I smooth my raw data using this function:

def _smooth(x, data_freq):
    LpFilt_cutoffFreq = 4
    LpFilt_order = 4
    lowpass_filter = scipy.signal.butter(
        LpFilt_order,
        LpFilt_cutoffFreq,
        fs=data_freq,
        output="sos",
    )
    result = scipy.signal.sosfiltfilt(lowpass_filter, x)
    return result

and one last time, during my analysis, I smooth the plot like this:

signal_avg_conv = np.convolve(signal_avg, np.ones(smoothbin) / smoothbin, 'same')

How can I know if my smoothing is causal?